Physical Sciences Division Research Highlights

May 2010

Graphene-DNA Biosensor Selective, Simple to Create

Nanostructure could help diagnose disease, facilitate gene therapy, more

An illustration of how fluorescent-tagged DNA interacts with functionalized graphene. Both single-stranded DNA (A) and double-stranded DNA (B) are adsorbed onto a graphene surface, but the interaction is stronger with ssDNA, causing the fluorescence on the ssDNA to darken more. C) A complimentary DNA nears the ssDNA and causes the adsorbed ssDNA to detach from the graphene surface. D) DNA adsorbed onto graphene is protected from being broken down. Enlarge Image

Graphene and DNA can combine to create a stable and accurate biosensor, reports a study published in the nanotechnology journal Small. The tiny biosensor might eventually help doctors and researchers better understand and diagnose disease.

Scientists at the Pacific Northwest National Laboratory and Princeton University showed that single-stranded DNA strongly interacts with graphene, a nanomaterial made of sheets of carbon atoms just a single atom thick. They also found that graphene protects DNA from being broken down by enzymes similar to those found in body fluids—a characteristic that should make graphene-DNA biosensors highly durable.

"Graphene is of great interest because it has several unique characteristics, including being easy and relatively inexpensive to make," said PNNL chemist Dr. Yuehe Lin, the paper's corresponding author. "But very few had systematically explored how graphene interacted with DNA using multiple spectroscopic techniques until we took a look. We found they make quite the pair."